1. Field
This document relates to a stereoscopic image display device.
2. Related Art
Techniques for stereoscopic image display devices are classified into a stereoscopic technique and an autostereoscopic technique.
The stereoscopic technique uses parallax images of the left and right eyes having a high three-dimensional effect and comprises a stereoscopic method and an autostereoscopic method both of which are being put to practical use. The stereoscopic method is used to display the left and right parallax images on a direct-view display device or a projector in a time-division manner or by changing the polarization directions of the left and right parallax images and to implement a stereoscopic image using the polarization glasses or the liquid crystal shutter glasses. In the autostereoscopic method, in general, a polarizing plate, such as a parallax barrier for separating the optical axes of the left and right parallax images, is placed in front or at the rear of a display screen.
In the stereoscopic method, a switching retarder for converting the polarization characteristic of light which is incident on the polarization glasses can be placed over the display device. The stereoscopic method is used to alternately display a left-eye image and a right-eye image on the display device and to convert the polarization characteristic of incident light on the polarization glasses through the switching retarder. Accordingly, the stereoscopic method can implement a stereoscopic image without a reduction in resolution by time-dividing the left-eye image and the right-eye image.
A liquid crystal display (LCD) can be used as a display device of the stereoscopic image display device. The LCD is configured to display an image by sequentially writing data from the first (top) line to the last (bottom) line of a screen. Meanwhile, a conventional stereoscopic image display device is driven in such a way that the on/off timings of a switchable retarder and scan electrodes formed in a display device (e.g., a liquid crystal display device) have the same duty ratio. When implementing the stereoscopic image display device, if the response characteristics of the on/off timings of the switchable retarder and the scan electrodes formed in the display device are asymmetrical to each other, there occurs a difference in the transmittance between the left eye and the right eye. Accordingly, the conventional stereoscopic image display device is required to solve crosstalk between a left-eye image and a right-eye image which occurs because of increasing intersection periods between the switchable retarder and the display device.